Shape Memory Alloy Actuators: A Review
Shrikant YadavInternational Journal for Research in Applied Science and Engineering Technology
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Abstract
The Shape memory alloys (SMAs) comes under special class of materials which possesses ability to recover their original shape at some temperatures characteristics. The SMAs are being used in different field in variety of applications. This ability of SMA can be viewed under high applied loads and elastic deformations. In this review paper, the SMA actuators and their applications are discussed. Keywords: SMA, Types of SMA, actuator. I. INTRODUCTION The term ''smart alloy'' was introduced in 1932 and the nomenclature ''shape-memory'' was given in 1941 for polymeric dental material [1, 2, 3]. Shape memory alloys (SMAs) are a unique type of material contains the ability to recover their shape at certain temperature characteristics. These materials are able to regain their original shape, even after reaching large inelastic deformations (near 10%) [1]. The demand for SMAs for engineering applications has been increasing in different fields; such as in industrial applications, automobile industries, aerospace applications, structures and composites, robotics and biomedical applications [4, 5]. Different SMA actuators like wire, compression / tension springs and cantilever had been used in thermal and electrical actuation systems [7, 33]. In this paper, a review on different applications of SMA actuators is presented.
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